CN207867015U - A kind of voltage transformer error electrification Compare System - Google Patents
A kind of voltage transformer error electrification Compare System Download PDFInfo
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- CN207867015U CN207867015U CN201721652939.1U CN201721652939U CN207867015U CN 207867015 U CN207867015 U CN 207867015U CN 201721652939 U CN201721652939 U CN 201721652939U CN 207867015 U CN207867015 U CN 207867015U
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Abstract
A kind of voltage transformer error electrification Compare System, including voltage compare sensor, compare signal processing unit, insulation column, mobile liftable device, Data Analysis Platform.It includes two open-close type capacitors, NPO capacitances, stray capacitance that the voltage, which compares sensor,.The open-close type capacitor is fixed on inside shielding case, open-close type capacitor is connected by shielded cable with NPO capacitances, NPO capacitances are located inside insulation column against the top, NPO capacitances lower end is connected in copper dish, the insulating gas of the pedestal and inside of copper dish and insulation column constitutes stray capacitance, insulating gas SF6.Temperature sensor is placed inside shielding case, inside insulation column.Tthe utility model system both can carry out error comparison to the voltage transformer that traditional analog amount exports, and can also carry out electrification comparison to the electronic mutual inductor and optical transformer of digital output, application range is very extensive.
Description
Technical field
A kind of voltage transformer error of the utility model charges Compare System, for constantly electric to operation in circuit
In voltage transformer carry out error comparison and trend prediction.
Background technology
Voltage transformer is one of the important measuring apparatus in electric system, in order to ensure the safety and stability fortune of electric system
Row, it is necessary to accurately monitoring be carried out in real time to the voltage of each key point of electric system, thus can't do without all kinds of voltage transformers.For
Ensure that the accuracy and reliability of voltage measurement, the performance that improves voltage transformer are extremely important.Wherein, voltage transformer
Error is to weigh an important indicator of voltage transformer performance.Under normal conditions, voltage transformer error test method is general
It is carried out at laboratory or scene out of service, circuit is exited since mutual inductor needs to have a power failure at this time, to save cost, Zhi Nengding
Phase overhaul, be unfavorable in real time observe mutual inductor operating status, can not find in time voltage transformer there are the problem of.As can
The real-time monitoring and trend prediction that transformer error is realized during mutual inductor on-line operation, then contribute to find in time mutual
Sensor there are the problem of, staff can also overhaul or replace to it in time.
It is compared for the error of voltage transformer and verification, Chinese patent " CN104916421A " provides a kind of high-precision
There are multiple pumpings in the parts such as polytropic ratio voltage transformer comparison device, including first winding, secondary winding and iron core in secondary winding
Head, each tap correspond to a change ratio, and whole device has multiple no-load voltage ratios, to realize different voltage outputs.However, the dress
It sets as currently used transformer checking system, the electrification that cannot achieve voltage transformer error compares.
Chinese patent " CN102645643A " provides a kind of electronic type voltage transformer on-line testing system, however, by
It is conventional electromagnetic voltage transformer in its standard mutual inductor, is induction equipment, and line facility is generally capacitive apparatus, so
There may be ferromagnetic resonances when band is electrically accessed, and there are larger security risks.In addition, increasing with voltage class, standard is mutual
Sensor volume and weight greatly increases, and is unfavorable for the scene electrification verification of voltage levels circuit.
Chinese patent " patent CN104034977A " provides a kind of 220kV capacitance type potential transformers live detection instrument,
Including several parts such as current unit, voltage cell, laptop.Voltage cell uses electromagnetic potential transformer, also deposits
In ferromagnetic resonance risk.When electrification compares, the accuracy of standard mutual inductor is the guarantee of comparison result accuracy, above several special
Profit, which does not take appropriate measures, ensures the measurement accuracy of standard mutual inductor.
In addition, the comparison mentioned in above several patents or calibration equipment, not to the error state of voltage transformer
Trend prediction and early warning are carried out, to be unfavorable for judgement and the decision of staff.
Invention content
At present for the comparison of the error of voltage transformer or check system, line outage is needed mostly, although by partly filling
Set may be implemented electrification verification, but existing ferromagnetic resonance risk, accuracy can not ensure, can not achieve Error Trend prediction and
The problems such as alarm, limits their application.To solve this problem, the utility model provides a kind of voltage transformer error
Charge Compare System.The system in the case where circuit charges, can realize that the electrification of voltage transformer error compares, and greatly simplify
Repair process, saves the cost of overhaul.The system both can carry out error comparison to the voltage transformer that traditional analog amount exports,
Electrification comparison can also be carried out to the electronic mutual inductor and optical transformer of digital output, application range is very extensive.
The technical solution that the utility model is taken is：
A kind of voltage transformer error electrification Compare System, including voltage compare sensor, compare signal processing unit, is exhausted
Edge pillar, mobile liftable device, Data Analysis Platform.It includes two open-close type capacitors, NPO electricity that the voltage, which compares sensor,
Hold, stray capacitance.
The open-close type capacitor is located above the support platform above insulation column, and open-close type capacitor is by two semi-rings
Shape cylinder is constituted, including inner ring, outer shroud, partition board are fixed and separated by partition board between inner ring and outer shroud, inner ring, outer shroud and
Intermediate gas constitutes gas capacitor, and inner ring, outer shroud are respectively the two-plate of gas capacitor；
The open-close type capacitor is fixed on inside shielding case, and open-close type capacitor passes through shielded cable and NPO electricity
Hold and be connected, NPO capacitances are located inside insulation column against the top, and NPO capacitances lower end is connected in copper dish, copper dish and insulation column
Pedestal and the insulating gas of inside constitute stray capacitance, insulating gas SF6；
Temperature sensor is placed inside shielding case, inside insulation column.
The open-close type capacitor adds accessory, and accessory is that hollow conductive material is made.
The open-close type capacitor connects elevating lever, is realized and is opened and closed by elevating lever.
The comparison signal processing unit includes Signal-regulated kinase, A/D conversion modules, microprocessor module, channel radio
Believe module, power module, voltage reference module, monitoring modular；
The open-close type capacitor, temperature sensor connection signal conditioning module, Signal-regulated kinase connect A/D moduluss of conversion
Block, A/D conversion modules connect microprocessor module, and microprocessor module connects wireless communication module；
Power module connects microprocessor module, and power module connects voltage reference module, monitoring modular.
Wireless communication module is connect with Data Analysis Platform wireless telecommunications.
The pedestal is connected to big ground by the ground terminal below mobile liftable device, and wheel is arranged at mobile liftable device lower part
Son.
The Data Analysis Platform includes hardware module, laptop；Hardware module compares signal processing for receiving
It unit and is compared the output data of mutual inductor, is sent out information；The warning information and be tested mutual that Data Analysis Platform is sent out
Sensor parameter information is sent to by hardware module on staff's mobile phone.
A kind of voltage transformer error of the utility model charges Compare System, and technique effect is as follows：
1), the voltage constituted using two open-close type capacitors and other additional devices compares sensor, is passed as standard
Sensor exports the form mutually compared using two open-close type capacitors, realizes sensor accuracy self-test, and utilize its output
Average value substantially increases as final output and compares accuracy and reliability.
2) temperature variations around three groups of voltage-dividing capacitors, are monitored in real time using temperature sensor, and then to sensing
The output of device carries out real time data compensation, substantially increases accuracy of measurement, table 1 statistics indicate that temperature to test result than poor shadow
The amount of sound is less than 0.015%, and angular difference influence amount is less than 0.8 '.
3) it, compares signal processing unit to be positioned in oval shielding case, can effectively reduce the electromagnetism from high-tension line
Interference.Circuit uses battery powered, power supply mode simple and reliable.When cell voltage will be insufficient, monitoring modular will send out announcement
Alert information, reminds staff to be replaced in time.
4), the use of voltage reference realizes System self-test, under system health, collected voltage reference pair
It is 0x8000 to answer digital quantity, and if not being this value, then explanation is likely to occur problem, and system sends out alarm signal, improves system work
Make reliability.
5), communication mode is wireless communication between partial devices of the system and secondary partial devices, avoids complexity
Connecting line, there is no Insulation Problems between primary equipment, secondary device, ensure that the safety of operating personnel.It is not required to simultaneously
Connecting line is wanted, the conveniently moving in the more power transformation stage space of equipment is tested convenient for the voltage transformer to different location.
6), the system can carry out trend prediction to tested transformer error state, estimate to be tested when mutual inductor can reach
Or be more than error limit, and staff is notified to carry out maintenance preparation in time, it improves work efficiency, avoids the hair of accident
It is raw.
7), the system installation operation is convenient, accuracy is high, and system global error is less than 0.05%.
8) pre- when, the system real-time judge voltage transformer operating status, predicted voltage mutual inductor reach error limit
Service life phase simultaneously can carry out early warning, and quality data support is provided for staff's maintenance.
Description of the drawings
Fig. 1 is that a kind of voltage transformer error of the utility model charges Compare System overall structure diagram.
Fig. 2 is that voltage compares sensor structure schematic diagram in the utility model.
Fig. 3 is that signal processing unit functional block diagram is compared in the utility model.
Specific implementation mode
A kind of voltage transformer error electrification Compare System includes mainly that voltage compares sensor 1, compares signal processing list
The parts such as member 2, insulation column 3, mobile liftable device 4, Data Analysis Platform 5.
Mobile liftable device 4 includes 3 section telescopic bars, is reduced to most 0.8 meter of short length, and length is up to 2 meters when elongation.It is flexible
Respectively there are one lead limit switch, telescopic rod runs to bottom or to after pushing up, and can be automatically stopped at bar both ends.Mobile liftable device 4 is adopted
With Alternating Current Power Supply, telescopic rod, which can only stretch, to be rotated.Wheel is arranged at 4 lower part of mobile liftable device, facilitates live movement.Such as Fig. 1
It is shown.Voltage compares the output of sensor 1 and sends comparison signal processing unit 2 to by shielded cable, through comparing signal processing list
After member 2, mode is sent to Data Analysis Platform 5 by radio communication.Data Analysis Platform 5 is used to compare sensor 1 to voltage
Oneself state, voltage transformer error state and its error change trend etc. carry out analyzing processing, and are reminded according to analysis result
Staff carries out maintenance preparation.
The voltage compares sensor 1 as shown in Fig. 2, by two open-close type capacitors 7, NPO capacitances 8, stray capacitance 9 etc.
Three groups of capacitances are constituted.Open-close type capacitor 7 is located above the support platform 6 of 3 top of insulation column, and support platform 6 is aluminium alloy
Material is made.The output result that voltage compares sensor 1 is the partial pressure of above three groups of capacitances as a result, taking on NPO capacitances 8
Voltage is as output voltage signal.8 value size of NPO capacitances is 100nF.In order to improve the accuracy of measurement result, two are utilized
The output result of open-close type capacitor 7 mutually compares, if its difference within 0.01%, illustrates that open-close type capacitor 7 closes
It closes well, position is normal, takes its average value as final result at this time；If difference is more than 0.01%, illustrate open-close type electricity
There is exception in container 7, staff is prompted to overhaul.This mode effectively increases the accuracy of comparison result and reliable
Property.Support platform 6 is made for aluminum alloy materials.
Open-close type capacitor 7 is made of two semi-circular cylinders 10, annular diameters 90mm, outer annular diameter 160mm, wide
Spend 30mm.It fixes and separates by partition board 11 between inner ring and outer shroud.Partition board 11 is insulating materials.Inner ring, outer shroud and centre
Gas constitutes gas capacitor, and inner ring and outer rings are respectively the two-plate of gas capacitor.
In order to adapt to the tested conducting wire of different-diameter, open-close type capacitor internal can be directed to different diameter of wire and install additional
Accessory 12, accessory 12 are that hollow conductive material is made.Open-close type capacitor is connected by shielded cable with NPO capacitances 8,
NPO capacitances 8 are located at 3 inside of insulation column against the top, and 8 lower end of NPO capacitances is connected in copper dish 13.Copper dish 13 and insulation column 3
The two poles of the earth as capacitance of pedestal 14, constitute stray capacitance 9, insulating gas SF with internal insulating gas6。
The open-close type capacitor 7 is fixed on inside shielding case 15, for reducing external disturbance.In order to reduce temperature
Change the influence to comparison result, inside shielding case 15, placed three temperature sensors 16 inside insulation column 3, be used for
The temperature value near three groups of capacitances is monitored, output result passes through cable transmission to comparison signal processing unit 2.Temperature sensor
16 output results finally carry out analyzing processing by Data Analysis Platform 5, real to be carried out to the voltage comparison output result of sensor 1
When compensation data, improve the accuracy of comparison result.Test result shows after compensation than poor influence amount less than 0.015%, angular difference
Influence amount is less than 0.8 '.
Open-close type capacitor 7 realizes folding using elevating lever 17, will first with mobile liftable device 4 when onsite application
Voltage compares sensor 1 and send to tested conducting wire, and then Data Analysis Platform 5 sends control information, controls open-close type capacitance
The folding of device 7 is sandwiched on tested conducting wire.Whole process, which realizes, to be automatically controlled, simple to operate.
2 functional block diagram of comparison signal processing unit is as shown in figure 3, the comparison signal processing unit 2 includes signal
Conditioning module, A/D conversion modules, microprocessor module, wireless communication module, power module, voltage reference module, monitoring mould
Block.Comparing signal processing unit 2, there are six the signals in channel altogether, including two outputs of open-close type capacitor 7, three temperature sensing
Device 16 exports and a voltage reference output signal.Voltage reference is generated by 2 internal electric source of comparison signal processing unit, and value is
Direct current 1.25V.After microprocessor module collects the signal of voltage reference, it is flat to be sent to data analysis for module by radio communication
Platform 5.Purpose using voltage reference be in order to realize System self-test, under system health, collected voltage reference
Corresponding digital quantity is 0x8000 (hexadecimal).It is this value such as to collect digital quantity not, then illustrates that internal system is likely to occur and ask
Topic, system alarm prompt staff overhaul.
The wireless communication module uses between GW-YL-5000 wireless communication modules, with Data Analysis Platform 5 without appointing
What directly connection, avoids the wiring of live complexity, at the same avoid be directly connected to may caused by Insulation Problems.
Signal processing unit 2 is compared to be positioned in oval shielding case.Since it is in high-pressure side, thus electromagnetic environment compared with
It is severe.Oval shielding case can effectively reduce electromagnetic interference, ensure to compare signal processing unit normal operation.It compares at signal
The power supply for managing unit 2 uses battery powered, and power supply mode is simple and reliable, and the service life was up to 1 year or more.When cell voltage will be insufficient
When, monitoring modular will send out warning information, and staff is reminded to be replaced in time.
Voltage reference module uses ADR421 chips, reference voltage 2.5V to generate the DC reference electricity of 1.25V after partial pressure
Pressure, for being compared with cell voltage.Monitoring modular realizes cell voltage and voltage reference using voltage comparator LM339
Comparison, cell voltage after partial pressure with supply voltage by being compared.Microprocessor module acquires the output of LM339 and to battery
Voltage judged, when brownout, send out warning information.
The pedestal 14 is connected to big ground by the ground terminal 18 below mobile liftable device 4.Under mobile liftable device 4
There is wheel in portion, convenient to move at the scene.For 4 range of mobile liftable device up to 6 meters or more, scene electrification can basis when comparing
The height of conducting wire is adjusted.
The Data Analysis Platform 5 is made of hardware module 19 and laptop 20, for receive data and to its into
Row analyzing processing.
There are three 19 major functions of hardware module：First, receiving the data for comparing signal processing unit 2, then pass through USB
Interface data is transmitted to laptop；Second is that receiving the output data for being compared mutual inductor, laptop is transmitted to by network interface；
Third, by the control of laptop, information is sent to staff's mobile phone.Core processor is using XILINX companies
FPGA (model XC5VLX110-2FFG1153I) carries out data processing.
The function of Data Analysis Platform 5 mainly has：
1) data, are received；
2) it, analyzes the output difference of two open-close type capacitors and carries out diversity judgement and alarm；
3), whether the collection capacity of analysis voltage benchmark is normal；
4) it, analyzes the output of three temperature sensors and real-time compensation is carried out to data；
5) it, receives and is compared the output signal of sensor and carries out data decoding, Parameter analysis；
6) it, calculates and is compared the parameters such as the amplitude, phase, error of sensor, and according to monitoring data to its error state
Trend prediction is carried out, the situation of change of transformer error is predicted, when may exceed error limit (± 0.2%) etc..
Hardware module 19 is other than for receiving comparison signal processing unit 2 and being compared the output data of mutual inductor, also
Information can be sent out.Warning information that Data Analysis Platform 5 is sent out and tested transformer parameter information etc. can pass through hardware
Module 19 is sent on staff's mobile phone, ensures that staff can receive information in time and handle.
Electrification Compare System software is formed using Labview software programmings, and program language is graphical language, writes letter
It is single.
A kind of voltage transformer error of the utility model charges Compare System, using two open-close type capacitors 7 and other
The voltage that additional device is constituted compares sensor 1 and is used as standard transducer, is exported using two open-close type capacitors 7 and mutually to be compared
Form realizes sensor accuracy self-test, and using the average value of its output as final output, it is accurate to substantially increase comparison
Degree and reliability.
The use of temperature sensor 16 can effectively reduce the influence of temperature change generation, be mended in real time to measurement data
It repays, to improve accuracy of measurement.
Table 1 be temperature-compensating before and compensation after charge Compare System error testing result figure
The result of table 1 also demonstrates this point.The system utilizes voltage reference and monitoring modular, realizes self performance
Self-test improves reliability.Meanwhile the system can carry out trend prediction to tested transformer error state, estimate to be tested mutual inductance
When device can meet or exceed error limit, and key parameter and warning information are timely transmitted to staff, make work people
Member carries out maintenance preparation in advance according to mutual inductor information, effectively increases working efficiency, avoids the generation of accident.The system is whole
Body error is less than 0.05%, and temperature is less than 0.015% to result than poor influence amount, and angular difference influence amount is less than 0.8 '.
Claims (5)
1. a kind of voltage transformer error charges Compare System, including voltage compares sensor（1）, compare signal processing unit
（2）, insulation column（3）, mobile liftable device（4）, Data Analysis Platform（5）；It is characterized in that：The voltage compares sensor
（1）Including two open-close type capacitors（7）, NPO capacitances（8）, stray capacitance（9）；The open-close type capacitor（7）Positioned at insulation
Pillar（3）The support platform of top（6）Above, open-close type capacitor（7）By two semi-circular cylinders（10）It constitutes, including interior
Ring, outer shroud, partition board（11）, pass through partition board between inner ring and outer shroud（11）It fixes and separates, inner ring, outer shroud and the gas of centre structure
At gas capacitor, inner ring, outer shroud are respectively the two-plate of gas capacitor；
The open-close type capacitor（7）It is fixed on shielding case（15）Inside, open-close type capacitor（7）By shielded cable with
NPO capacitances（8）It is connected, NPO capacitances（8）Positioned at insulation column（3）It is internal against the top, NPO capacitances（8）Lower end is connected to copper dish
（13）On, copper dish（13）With insulation column（3）Pedestal（14）And internal insulating gas constitutes stray capacitance（9）, insulation
Gas is SF6；
In shielding case（15）Internal, insulation column（3）Inside placed temperature sensor（16）；
The Data Analysis Platform（5）Including hardware module（19）, laptop（20）；
Hardware module（19）Signal processing unit is compared for receiving（2）Be compared the output data of mutual inductor, be sent out
Information；Data Analysis Platform（5）The warning information sent out and tested transformer parameter information, pass through hardware module（19）It is sent to
On staff's mobile phone.
2. a kind of voltage transformer error charges Compare System according to claim 1, it is characterised in that：The open-close type electricity
Container（7）Add accessory（12）, accessory（12）It is made for hollow conductive material.
3. a kind of voltage transformer error charges Compare System according to claim 1, it is characterised in that：The open-close type electricity
Container（7）Connect elevating lever（17）, pass through elevating lever（17）Realize folding.
4. a kind of voltage transformer error charges Compare System according to claim 1, it is characterised in that：The comparison signal
Processing unit（2）Including Signal-regulated kinase, A/D conversion modules, microprocessor module, wireless communication module, power module, electricity
Press base modules, monitoring modular；
The open-close type capacitor（7）, temperature sensor（16）Connection signal conditioning module, Signal-regulated kinase connect A/D and turn
Block is changed the mold, A/D conversion modules connect microprocessor module, and microprocessor module connects wireless communication module；
Power module connects microprocessor module, and power module connects voltage reference module, monitoring modular；
Wireless communication module and Data Analysis Platform（5）Wireless telecommunications connect.
5. a kind of voltage transformer error charges Compare System according to claim 1, it is characterised in that：The pedestal（14）
Pass through mobile liftable device（4）Following ground terminal（18）It is connected to big ground, mobile liftable device（4）Wheel is arranged at lower part.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721652939.1U CN207867015U (en) | 2017-12-01 | 2017-12-01 | A kind of voltage transformer error electrification Compare System |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721652939.1U CN207867015U (en) | 2017-12-01 | 2017-12-01 | A kind of voltage transformer error electrification Compare System |
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| Publication Number | Publication Date |
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| CN207867015U true CN207867015U (en) | 2018-09-14 |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107991642A (en) * | 2017-12-01 | 2018-05-04 | 三峡大学 | A kind of powered Compare System of voltage transformer error |
| CN113311299A (en) * | 2021-05-26 | 2021-08-27 | 广西电网有限责任公司南宁供电局 | CVT insulation defect detection method and device |
-
2017
- 2017-12-01 CN CN201721652939.1U patent/CN207867015U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107991642A (en) * | 2017-12-01 | 2018-05-04 | 三峡大学 | A kind of powered Compare System of voltage transformer error |
| CN113311299A (en) * | 2021-05-26 | 2021-08-27 | 广西电网有限责任公司南宁供电局 | CVT insulation defect detection method and device |
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